<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
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  <title>Document</title>
</head>

<body>
  <script>
    let age = 5
    let year = +prompt('请输入您的年龄')
    let sum = age + year
    console.log(`据我估计,五年后,你可能${sum}岁了`);
  </script>
</body>

</html>